I did this: updated WordPress to the last version (3.5). Everything was working perfectly before the update.

My main problem is that the title of my home page is not rewritten properly. It displays "Blog - eduPad" instead of "Education apps for tablets and smartphones - eduPad"

This problem disappears when I uncheck the option "Force rewrite titles" in WordPress SEO settings. However, when I uncheck this option, my sitename is duplicated at the end of every title. For exemple, I get "Contact us | eduPadeduPad" instead of "Contact us | eduPad".